ENTOMOLOGY 341 



all kinds. The excretory and shed refuse matter in a neglected 

 kennel or box, or on a sleeping rug, offer ideal conditions; but a 

 little heap of moist v sawdust, or even the dust and dirt in the 

 spaces between flood boards, will answer as well. It usually takes 

 about ten days or two weeks for these larvae to become full grown, 

 and then they spin thin silken cocoons, in which they change to 

 pupae. In less than a week, usually, they complete the change to 

 adults, and these seem to be able to reproduce without blood food. 



House infestation usually comes when the place is shut up 

 early in summer and the sleeping quarters of the dog or cat are left 

 as they stand. Unless the animals using the bed were absolutely 

 without fleas, eggs or larvae are almost certain to be present, and 

 these are thus enabled to mature undisturbed. The resulting adults 

 will scatter in their search for food, and later broods of larvae will 

 develop in organic matter anywhere throughout the house. Dur- 

 ing a two months' vacation three broods may develop, and the re- 

 turning family will then find matters lively in more ways than 

 one. Usually the lowest floor is worst infested, and rarely do the 

 insects get above the second story. 



As the family pets are primarily responsible for the infestation, 

 they can be made use of to reduce it, using the preference of the 

 fleas for such animals as the lure. First wash the animal with car- 

 bolic soap to destroy all the insects then infesting it dogs are 

 easier to wash than cats, and the latter may be thoroughly dusted 

 with fresh pyrethrum well rubbed into the fur instead then allow 

 the animal to run throughout the infested part of the house for 

 twenty-four hours; wash or dust against to destroy the new infesta- 

 tion, and continue this until all the adults have been trapped and 

 destroyed. Meanwhile clean thoroughly all the infested rooms 

 and remove every accumulation of organic matter that might pos- 

 sibly serve as breeding place for the larvae. Floors should be 

 scrubbed or mopped, and then, after they are dry, gasoline should 

 be run into every crack between boards and under baseboards to 

 kill larvae and pupae. In the infested laboratory ten gallons were 

 used in two days, but at the end of that time there were mighty 

 few fleas left and no larvae remained to provide for a new supply. 

 The flea larvae seem to require undisturbed conditions for their 

 proper development, hence they never multiply greatly, if at all, 

 in rooms or places that are frequently cleaned, swept or disturbed. 



The bed, box or other resting place of the house dog or cat 

 should be cleaned or shaken out and exposed to the sunlight at least 

 once in ten days, and better once a week. 



Lice. These are, more strictly speaking, parasites, infesting 

 both man and domestic animals; but as certain species are almost 

 or quite confined to man, and as children may become infested from 

 casual playmates, a few words on the subject may not be amiss. 



The commonest species is the so-called head-louse, which de- 

 rives its name from the fact that it is most generally found among 

 the hair of the head and feeds by puncturing the skin and sucking 

 blood. The eggs are attached to the hair, and so tightly that ordi- 



